Known in the prior art are aircraft wheel and brake assemblies including a non-rotatable wheel support, a wheel mounted to the wheel support for rotation, and a brake disk stack having front and rear axial ends and alternating rotor and stator disks mounted with respect to the wheel support and wheel for relative axial movement. Each rotor disk is coupled to the wheel for rotation therewith and each stator disk is coupled to the wheel support against rotation. A back plate is located at the rear end of the disk pack and a brake head is located at the front end. The brake head houses a plurality of actuator rams that extend to compress the brake disk stack against the back plate. Torque is taken out by the stator disks through a static torque tube or the like.
As the brake disks wear, the running clearance of the actuator rams correspondingly increases. To maintain an acceptable running clearance, mechanical adjustor devices have been employed. While functional, these devices add weight and complexity to the braking system, and need to be overhauled usually each time the brake disk stack is replaced. For at least these reasons, it would be desirable to provide for running clearance adjustment without the need for these mechanical adjustor devices.
Present day aircraft brake systems also have employed wear pin indicators to measure overall wear of the brake disk stack. Brake wear is indicated by the length of the pin relative to a reference plate. This arrangement requires a visual inspection of the pin to determine wear and is inherently imprecise. It would be desirable to provide for brake wear measurement without the need for a visual inspection and with greater precision.
Moreover, it would be desirable to provide for brake actuator running clearance and brake wear indication utilizing means that may be interfaced into an electro-mechanical brake system. Electro-mechanical braking systems eliminate drawbacks associated with hydraulic braking systems such as fluid leaks, high maintenance requirements, fire hazard and higher overall weight.